library(mirai)

a <- 1
b <- 2

m <- mirai(
  {
    Sys.sleep(5)
    a + b
  },
  environment()
)

m
#> < mirai | $data >

m$data
#> 'unresolved' logi NA

m[]
#> [1] 3

m$data
#> [1] 3

library(shiny)
library(bslib)
library(mirai)

ui <- page_fluid(
  numericInput("n", "Sample size (n)", 100),
  numericInput("delay", "Seconds to take for plot", 5),
  input_task_button("btn", "Plot uniform distribution"),
  plotOutput("plot")
)

server <- function(input, output, session) {
  task <- ExtendedTask$new(
    function(...) mirai({Sys.sleep(y); runif(x)}, ...)
  ) |> bind_task_button("btn")
  observeEvent(input$btn, task$invoke(x = input$n, y = input$delay))
  output$plot <- renderPlot(hist(task$result()))
}

app <- shinyApp(ui = ui, server = server)
with(daemons(3), runApp(app))

library(plumber)
library(promises)
library(mirai)

pr() |>
  pr_get(
    "/echo",
    function(req, res) {
      mirai(
        list(status = 200L, body = list(msg = msg)),
        msg = req[["HEADERS"]][["msg"]]
      ) %...>% (function(x) {
          res$status <- x$status
          res$body <- x$body
        })
    }
  ) |>
  pr_run(host = "127.0.0.1", port = 8985)